net.sf.saxon.s9api

## Class DocumentBuilder

- java.lang.Object
- - net.sf.saxon.s9api.DocumentBuilder

-     public class DocumentBuilder
      extends Object

  A document builder holds properties controlling how a Saxon document tree should be built, and provides methods to invoke the tree construction.

  This class has no public constructor. Users should construct a DocumentBuilder by calling the factory method `Processor.newDocumentBuilder()`.

  All documents used in a single Saxon query, transformation, or validation episode must be built with the same `Configuration`. However, there is no requirement that they should use the same `DocumentBuilder`.

  Sharing of a `DocumentBuilder` across multiple threads is not recommended. However, in the current implementation sharing a `DocumentBuilder` (once initialized) will only cause problems if a `SchemaValidator` is used.

  Since:
    9.0

- - ### Constructor Summary

    Constructors
    Modifier | Constructor and Description
    --- | ---
    `protected` | `DocumentBuilder(Configuration config)` Create a DocumentBuilder.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `XdmNode` | `build(File file)` Build a document from a supplied XML file
    `XdmNode` | `build(Source source)` Load an XML document, to create a tree representation of the document in memory.
    `URI` | `getBaseURI()` Get the base URI of documents loaded using this DocumentBuilder when no other URI is available.
    `XQueryExecutable` | `getDocumentProjectionQuery()` Get the compiled query to be used for implementing document projection.
    `SchemaValidator` | `getSchemaValidator()` Get the SchemaValidator used to validate documents loaded using this `DocumentBuilder`.
    `TreeModel` | `getTreeModel()` Get the tree model to be used for documents constructed using this DocumentBuilder.
    `WhitespaceStrippingPolicy` | `getWhitespaceStrippingPolicy()` Get the white whitespace stripping policy applied when loading a document using this `DocumentBuilder`.
    `boolean` | `isDTDValidation()` Ask whether DTD validation is to be applied to documents loaded using this `DocumentBuilder`
    `boolean` | `isLineNumbering()` Ask whether line numbering is enabled for documents loaded using this `DocumentBuilder`.
    `BuildingContentHandler` | `newBuildingContentHandler()` Get an `ContentHandler` that may be used to build the document programmatically.
    `BuildingStreamWriterImpl` | `newBuildingStreamWriter()` Get an `XMLStreamWriter` that may be used to build the document programmatically.
    `void` | `setBaseURI(URI uri)` Set the base URI of a document loaded using this `DocumentBuilder`.
    `void` | `setDocumentProjectionQuery(XQueryExecutable query)` Set a compiled query to be used for implementing document projection.
    `void` | `setDTDValidation(boolean option)` Set whether DTD validation should be applied to documents loaded using this `DocumentBuilder`.
    `void` | `setLineNumbering(boolean option)` Say whether line numbering is to be enabled for documents constructed using this DocumentBuilder.
    `void` | `setSchemaValidator(SchemaValidator validator)` Set the schemaValidator to be used.
    `void` | `setTreeModel(TreeModel model)` Set the tree model to be used for documents constructed using this DocumentBuilder.
    `void` | `setWhitespaceStrippingPolicy(WhitespaceStrippingPolicy policy)` Set the whitespace stripping policy applied when loading a document using this `DocumentBuilder`.
    `XdmNode` | `wrap(Object node)` Create a node by wrapping a recognized external node from a supported object model.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### DocumentBuilder

          protected DocumentBuilder(Configuration config)

      Create a DocumentBuilder. This is a protected constructor. Users should construct a DocumentBuilder by calling the factory method `Processor.newDocumentBuilder()`.
      Parameters:
        `config` - the Saxon configuration

  - ### Method Detail

    - #### setTreeModel

          public void setTreeModel(TreeModel model)

      Set the tree model to be used for documents constructed using this DocumentBuilder. By default, the TinyTree is used (irrespective of the TreeModel set in the underlying Configuration).
      Parameters:
        `model` - typically one of the constants `TreeModel.TINY_TREE`, `TreeModel.TINY_TREE_CONDENSED`, or `TreeModel.LINKED_TREE`. It can also be an external object model such as `XOMObjectModel`
      Since:
        9.2

    - #### getTreeModel

          public TreeModel getTreeModel()

      Get the tree model to be used for documents constructed using this DocumentBuilder. By default, the TinyTree is used (irrespective of the TreeModel set in the underlying Configuration).
      Returns:
        the tree model in use: typically one of the constants `TreeModel.TINY_TREE`, `TreeModel.TINY_TREE_CONDENSED`, or `TreeModel.LINKED_TREE`. However, in principle a user-defined tree model can be used.
      Since:
        9.2

    - #### setLineNumbering

          public void setLineNumbering(boolean option)

      Say whether line numbering is to be enabled for documents constructed using this DocumentBuilder. This has the effect that the line number in the original source document is maintained in the constructed tree, for each element node (and only for elements). The line number in question is generally the line number on which the closing ">" of the element start tag appears.

      By default, line numbers are not maintained.

      Errors relating to document parsing and validation will generally contain line numbers whether or not this option is set, because such errors are detected during document construction.

      Line numbering is not available for all kinds of source: for example, it is not available when loading from an existing DOM Document.

      The resulting line numbers are accessible to applications using the XPath extension function saxon:line-number() applied to a node, or using the Java method `NodeInfo.getLineNumber()`

      Line numbers are maintained only for element nodes; the line number returned for any other node will be that of the most recent element. For an element node, the line number is generally that of the closing angle bracket at the end of the start tag (this is what a SAX parser notifies)

      Parameters:
        `option` - true if line numbers are to be maintained, false otherwise.

    - #### isLineNumbering

          public boolean isLineNumbering()

      Ask whether line numbering is enabled for documents loaded using this `DocumentBuilder`.

      By default, line numbering is disabled.

      Line numbering is not available for all kinds of source: in particular, it is not available when loading from an existing XmlDocument.

      The resulting line numbers are accessible to applications using the extension function saxon:line-number() applied to a node, or using the Java method `NodeInfo.getLineNumber()`

      Line numbers are maintained only for element nodes; the line number returned for any other node will be that of the most recent element. For an element node, the line number is generally that of the closing angle bracket at the end of the start tag (this is what a SAX parser notifies)

      Returns:
        true if line numbering is enabled

    - #### setSchemaValidator

          public void setSchemaValidator(SchemaValidator validator)

      Set the schemaValidator to be used. This determines whether schema validation is applied to an input document and whether type annotations in a supplied document are retained. If no schemaValidator is supplied, then schema validation does not take place.

      This option requires the schema-aware version of the Saxon product (Saxon-EE).

      Since a `SchemaValidator` is serially reusable but not thread-safe, using this method is not appropriate when the `DocumentBuilder` is shared between threads.

      Parameters:
        `validator` - the SchemaValidator to be used

    - #### getSchemaValidator

          public SchemaValidator getSchemaValidator()

      Get the SchemaValidator used to validate documents loaded using this `DocumentBuilder`.
      Returns:
        the SchemaValidator if one has been set; otherwise null.

    - #### setDTDValidation

          public void setDTDValidation(boolean option)

      Set whether DTD validation should be applied to documents loaded using this `DocumentBuilder`.

      By default, no DTD validation takes place.

      Parameters:
        `option` - true if DTD validation is to be applied to the document

    - #### isDTDValidation

          public boolean isDTDValidation()

      Ask whether DTD validation is to be applied to documents loaded using this `DocumentBuilder`
      Returns:
        true if DTD validation is to be applied

    - #### setWhitespaceStrippingPolicy

          public void setWhitespaceStrippingPolicy(WhitespaceStrippingPolicy policy)

      Set the whitespace stripping policy applied when loading a document using this `DocumentBuilder`.

      By default, whitespace text nodes appearing in element-only content are stripped, and all other whitespace text nodes are retained.

      Parameters:
        `policy` - the policy for stripping whitespace-only text nodes from source documents

    - #### getWhitespaceStrippingPolicy

          public WhitespaceStrippingPolicy getWhitespaceStrippingPolicy()

      Get the white whitespace stripping policy applied when loading a document using this `DocumentBuilder`.
      Returns:
        the policy for stripping whitespace-only text nodes

    - #### setBaseURI

          public void setBaseURI(URI uri)

      Set the base URI of a document loaded using this `DocumentBuilder`.

      This is used for resolving any relative URIs appearing within the document, for example in references to DTDs and external entities.

      This information is required when the document is loaded from a source that does not provide an intrinsic URI, notably when loading from a Stream or a DOMSource. The value is ignored when loading from a source that does have an intrinsic base URI.

      Parameters:
        `uri` - the base URI of documents loaded using this `DocumentBuilder`. This must be an absolute URI.
      Throws:
        `IllegalArgumentException` - if the baseURI supplied is not an absolute URI

    - #### getBaseURI

          public URI getBaseURI()

      Get the base URI of documents loaded using this DocumentBuilder when no other URI is available.
      Returns:
        the base URI to be used, or null if no value has been set.

    - #### setDocumentProjectionQuery

          public void setDocumentProjectionQuery(XQueryExecutable query)

      Set a compiled query to be used for implementing document projection. The effect of using this option is that the tree constructed by the DocumentBuilder contains only those parts of the source document that are needed to answer this query. Running this query against the projected document should give the same results as against the raw document, but the projected document typically occupies significantly less memory. It is permissible to run other queries against the projected document, but unless they are carefully chosen, they will give the wrong answer, because the document being used is different from the original.

      The query should be written to use the projected document as its initial context item. For example, if the query is `//ITEM[COLOR='blue')`, then only `ITEM` elements and their `COLOR` children will be retained in the projected document.

      This facility is only available in Saxon-EE; if the facility is not available, calling this method has no effect.

      Parameters:
        `query` - the compiled query used to control document projection
      Since:
        9.3

    - #### getDocumentProjectionQuery

          public XQueryExecutable getDocumentProjectionQuery()

      Get the compiled query to be used for implementing document projection.
      Returns:
        the query set using `setDocumentProjectionQuery(net.sf.saxon.s9api.XQueryExecutable)` if this has been called, or null otherwise
      Since:
        9.3. In 9.4 the unused and undocumented first argument is removed.

    - #### build

          public XdmNode build(Source source)
                        throws SaxonApiException

      Load an XML document, to create a tree representation of the document in memory.
      Parameters:
        `source` - A JAXP Source object identifying the source of the document. This can always be a `StreamSource` or a `SAXSource`. Some kinds of Source are consumed by this method, and should only be used once.

        If a SAXSource is supplied, the XMLReader held within the SAXSource may be modified (by setting features and properties) to reflect the options selected on this DocumentBuilder.

        An instance of `DOMSource` is accepted provided that the Saxon support code for DOM (in saxon9-dom.jar) is on the classpath.

        If the source is an instance of `NodeInfo` then the subtree rooted at this node will be copied (applying schema validation if requested) to create a new tree.

        Saxon also accepts an instance of `StAXSource` or `PullSource`, which can be used to supply a document that is to be parsed using a StAX parser.

        (9.2) This method no longer accepts an instance of `AugmentedSource`, because of confusion over interactions between the properties of the AugmentedSource and the properties of this DocumentBuilder.

      Returns:
        An `XdmNode`. This will be the document node at the root of the tree of the resulting in-memory document.
      Throws:
        `NullPointerException` - if the source argument is null
        `IllegalArgumentException` - if the kind of source is not recognized
        `SaxonApiException` - if any other failure occurs building the document, for example a parsing error

    - #### build

          public XdmNode build(File file)
                        throws SaxonApiException

      Build a document from a supplied XML file
      Parameters:
        `file` - the supplied file
      Returns:
        the XdmNode representing the root of the document tree
      Throws:
        `SaxonApiException` - if any failure occurs retrieving or parsing the document

    - #### newBuildingContentHandler

          public BuildingContentHandler newBuildingContentHandler()
                                                           throws SaxonApiException

      Get an `ContentHandler` that may be used to build the document programmatically.
      Returns:
        a newly constructed `BuildingContentHandler`, which implements the `ContentHandler` interface. If schema validation has been requested for this `DocumentBuilder`, then the document constructed using the `ContentHandler` will be validated as it is written.

        Note that the returned `ContentHandler` expects namespace scopes to be indicated explicitly by calls to `ContentHandler.startPrefixMapping(java.lang.String, java.lang.String)` and `ContentHandler.endPrefixMapping(java.lang.String)`.

        If the stream of events supplied to the `ContentHandler` does not constitute a well formed (and namespace-well-formed) document, the effect is undefined; Saxon may fail to detect the error, and construct an unusable tree.

      Throws:
        `SaxonApiException` - if any failure occurs
      Since:
        9.3

    - #### newBuildingStreamWriter

          public BuildingStreamWriterImpl newBuildingStreamWriter()
                                                           throws SaxonApiException

      Get an `XMLStreamWriter` that may be used to build the document programmatically.
      Returns:
        a newly constructed `BuildingStreamWriter`, which implements the `XMLStreamWriter` interface. If schema validation has been requested for this `DocumentBuilder`, then the document constructed using the `XMLStreamWriter` will be validated as it is written.

        If the stream of events supplied to the `XMLStreamWriter` does not constitute a well formed (and namespace-well-formed) document, the effect is undefined; Saxon may fail to detect the error, and construct an unusable tree.

      Throws:
        `SaxonApiException` - if any failure occurs
      Since:
        9.3

    - #### wrap

          public XdmNode wrap(Object node)
                       throws IllegalArgumentException

      Create a node by wrapping a recognized external node from a supported object model.

      If the supplied object implements the `NodeInfo` interface then it will be wrapped as an `XdmNode` without copying and without change. The `NodeInfo` must have been created using a `Configuration` compatible with the one used by this `Processor` (specifically, one that uses the same `NamePool`)

      To wrap nodes from other object models, such as DOM, the support module for the external object model must be on the class path and registered with the Saxon configuration. The support modules for DOM, JDOM, DOM4J and XOM are registered automatically if they can be found on the classpath.

      It is best to avoid calling this method repeatedly to wrap different nodes in the same document. Each such wrapper conceptually creates a new XDM tree instance with its own identity. Although the memory is shared, operations that rely on node identity might not have the expected result. It is best to create a single wrapper for the document node, and then to navigate to the other nodes in the tree using S9API interfaces.

      Parameters:
        `node` - the node in the external tree representation. Either an instance of `NodeInfo`, or an instances of a node in an external object model. Nodes in other object models (such as DOM, JDOM, etc) are recognized only if the support module for the external object model is known to the Configuration.
      Returns:
        the supplied node wrapped as an XdmNode
      Throws:
        `IllegalArgumentException` - if the type of object supplied is not recognized. This may be because node was created using a different Saxon Processor, or because the required code for the external object model is not on the class path

Copyright (c) 2004-2013 Saxonica Limited. All rights reserved.